Press feeding

ABSTRACT

A two-position cycle selector operates a control valve to control operation of a press feed device in either of two opposite direction. Each of two fluid outlets of the control valve is opened and closed in response to movements of the press. One of the outlets is connected to each of two locking flanges which alternately lock the strip material fed to the press and is also connected to a stop valve. The other outlet is connected to the stop valve and operation of the selector selectively blocks the intake of fluid to the stop valve from each of the control outlets in accordance with the position of the stop valve.

United States Patent Inventor Roger Jean Pinat 9, rue des Capucines, 78 Poissy, France Appl. No. 847,093 Filed Aug. 4, 1969 Patented Dec. 14, 1971 Priority Aug. 2, 1968 France 161,64 1

PRESS FEEDING 1 Claim, 6 Drawing Figs.

US. Cl 83/277, 226/49 Int. Cl B65l1 17/34 Field of Search 83/277; 226/49 [56] References Cited UNlTED STATES PATENTS 2,749,981 6/1956 MacKinnon et al. 83/277 X 3,512,438 5/1970 Burdge 83/277 X Primary Examiner-James M. Meister A ttorney-Watson, Cole, Grindle & Watson ABSTRACT: A two-position cycle selector operates a control valve to control operation of a press feed device in either of two opposite direction. Each of two fluid outlets of the control valve is opened and closed in response to movements of the press. One of the outlets is connected to each of two locking flanges which alternately lock the strip material fed to the press and is also connected to a stop valve. The other outlet is connected to the stop valve and operation of the selector selectively blocks the intake of fluid to the stop valve from each of the control outlets in accordance with the position of the stop valve.

Patented Dec; 14, 1971 3,626,790

2 Sheets-Shoot 1 Fm d. 2 [1w zdnbg I PRESS FEEDING This invention relates to feed presses and, more particularly, to such presses, wherein a feed device causes the strip to advance in either one or the other of two directions.

In existing presses operating on strip material, whether metal or otherwise, which are fed step by step, the feed device is made to cause the strip to advance in only one direction, i.e., to shove it toward the press, or else to withdraw it. Some presses are provided with two such devices making it possible to work one by pushing and the other by drawing.

The improved press of this invention comprises a control valve of particular shape and a two position cycle selector which operates a feed device to cause it to operate either in one direction or the other by a simple manipulation of the selector.

It is an object of this invention to provide a single feed device for shoving strip material forward in one direction or to withdraw the strip material in the opposite direction.

The objects, characteristics and advantages of the invention will be more clearly understood by the following description with reference to the accompanying drawings which represent an exemplary embodimentfor carrying out the invention.

With reference to the drawings:

FIG. 1 illustrates a pneumatic feed device according to the invention;

FIG. 2 is a sectional view of a jack for moving a strip of material;

FIG. 3 represents a section of a control valve according to the invention;

FIG. 3A represents a section of a prior art control valve used in existing feed devices;

FIG. 4 is a partial sectional view of a control piston for a mobile flange; and

FIG. 5 is a partial sectional view of a control piston for a stationary flange.

The feed device described herein comprises a known rigid jack with a mobile flange, and a fixed flange, both operating to lock, in turn, working strip B. When the mobile flange locks the strip, the jack travels to make it advance a step, then the stationary flange assures the locking of the strip while the press performs its work. The mobile flange unlocks to permit the jack to recommence the cycle again in the opposite direction along a length of the strip equal to a step.

In FIG. 1, a standard compressed air intake, with valve cock R, filter F, monopressure reducer MD air greaser G and rapid connector RR, constantly feeds back compartment AR of a jack I, upper compartments H of two control pistons 2 of the stationary flange, two shock absorbers of mobile flange 3, and the back part AR of stop valve 4. Air delivery pipes for the two control pistons 5 of the mobile flange for the lower compartments B of pistons 2 of the stationary flange and for a restarter of mobile flange 6 are controlled by two position valves 7. An air delivery pipe for the front part AV of stop valve 4 is controlled by valve 7 and cycle selector 8. As will be more fully described hereinafter, when part AV of the stop valve is in the exhaust position, the air supplied to its part AR reaches compartment AV of jack 1. Conversely, when part AV of the stop valve is fed, part AV of the jack is in the exhaust position. Selector 8 has two positions, represented symbolically side by side in the drawing, 8? and ST corresponding respectively to shoving and drawing feed movement.

In FIG. 2, rod 9 of jack 1, the travel of which is limited by stop I0, is rigidly connected to block 11 on which is mounted mobile flange l2. Stationary flange 13 is mounted above cylinder 14, the back and front compartments of which are fed respectively by air intake 15 which communicates directly with the air source, and by air intake 16 controlled by valve 7. The front face of piston l' is larger than its back face and this piston moves backward or forward, depending on whether air supply pipe 16 is fed or not.

FIG. 3A represents a known control valve, corresponding to control valve 7 in FIG. 1 in open position, used in existing feed devices. An air intake 17 communicates with outlet 18 by means of a passage controlled by clack valve 19, stopping of the passage being assured by a cut part 20 of clack valve 19. Clack valve 19 is mounted at the end of rod 21, provided on the opposite end with piston 22 housed in cylinder 23, and fed air by conduit 24 made in the axis of rod 21. When operating, the valve is constantly fed air and piston 22 is flat at the bottom of cylinder 23. To close the valve, a transmission controlled by the movements of the press acts on the cylinder downward in the direction of arrow f. Outlet 18 communicates with pistons 5 of the mobile flange, lower side B of pistons 2 of the stationary flange, and the front part of stop valve 4, selector 8 being nonexistent in this apparatus.

In FIG. 3, valve 7, according to the invention, has elements 17', 18, 19, 20, 21', 22', 23, equivalent to those of FIG. 3A designated by the same numbers without the prime mark. However, in the case of valve 7, rod 21' extends downward by rod 24 which ends in a second clack valve 25, operating a second outlet 26. Outlet 26 communicates with the front part of stop valve 4, by means of cycle selector 8, while outlet 18 communicates directly with elements 2, 5, 6, and also with the front part of the stop valve by means of cycle selector 8 (FIG. I

Cycle selector 8 is an apparatus with two positions, shoving and drawing, and operates to put the front part of stop valve 4 in communication with only one of two air outlets I8, 26, namely, outlet 18 in the shoving position and outlet 26 in the drawing position.

In FIG. 4, mobile flange 12 is mounted on the ends of two rods 27 (only one of which is represented in the drawing), each controlled by a piston 28. When air intake 29, controlled by valve 7, sends air to pistons 28, flange l2 lowers into the locking position. When the pistons are in the exhaust position, it rises under the action of recall springs 30.

Stationary flange 13, which can be seen in the partial view of FIG. 5, is mounted on the end of two rods 31 (only one of which is represented in the drawing) each controlled by a piston 32 with differential action. Air intakes 33, 34 send the air respectively to the upper and lower faces of piston 34, the lower face being the larger of the two. Air intake 33, connected directly to the air source, is fed constantly, while intake 34 is controlled by valve 7. Depending on whether the lower face of piston 32 is fed air or is put in the exhaust position, flange l3 rises or descends.

Stop valve 4 is a known type of slide valve whose front and back parts are fed, respectively, by means of the valve and cycle selector and by the air source. When the front part is in the exhaust position, the slide valve moves forward and opens a passage, causing the air to arrive from its part AR to intake 16 of the front compartment of jack 1. When the front part of the stop valve is fed air by the valve, the slide comes backward by the differential pressure and blocks this passage.

The description of the mode of operation of a known type of shoving feed using a known valve without a selector will aid in understanding the invention. When the plates of the press are moved away from each other, valve 2 is in the high position. As can be seen from what has been said, mobile flange 12 is locked, stationary flange 13 is lifted, the intake of air to the front part of the stop valve 4 closes the latter, the front chamber of the cylinder is in the exhaust position and the jack moves forward to move strip B a step. The press going into action lowers valve 7, which puts the chambers of the pistons of the mobile flange, the lower sides of the pistons of the stationary flange and the front part of stop valve 4 in the exhaust position. The mobile flange rises by the action of a recall spring and the stationary flange locks the strip. The press performs its work and the stop valve opens to send the air to the front compartment of jack 1, which thus comes back to recommence the cycle.

I. SHOVING FEED Cycle selector 8 makes the passage between air outlet 18' of valve 7 and the front part of stop valve 4, while the passage between this latter valve and outlet 26 is blocked. The operations are performed in the order indicated above for the regular shoving feed.

ll. DRAWING FEED Cycle selector 8 makes the passage between air outlet 26 and the front part of stop valve 4, while the passage between this latter valve and outlet 18 is blocked. The press plates are separated from one another and valve 7 is at the high point. The mobile flange is locked, the stationary flange has been lifted, but stop valve 4 is open, because its front part is in the exhaust position. The jack moves backward to draw the strip a step backward, When the press plates come toward one another, valve 7 goes down, outlet 18' is blocked, the mobile flange rises under the action of springs 30, the stationary flange goes down and locks the strip to keep it immobile while the press performs its work. In addition, the movement of the valve downward uncovers air outlet 26 which feeds the front part of stop valve 4. This latter closes, the front chamber of jack 1 is in the exhaust position and the jacket returns forward to seek a new length of strip and to recommence the drawing cycle.

In the case of a shoving feed, it is necessary to clamp the full strip which, in certain cases, marks the pieces. Drawing feed presents the advantage of clamping the framework of the strip which avoids marking of the pieces. In the case of strip cutting, mounting of the two feeds, located on each side of the took, is possible; one feed shoving and the other feed drawing. All handling at the beginning and end of the strip is thereby avoided.

The invention therefore provides an easy means to facilitate the operation of strip feed presses. lt is possible to make modifications in the invention described above. For example, the controls operated by constant feeding of fluid under pressure can be replaced by any equivalent means, such as springs.

I claim:

1. In a device for feeding strip material to a press having two locking flanges for alternately locking the strip, a jack for moving said flanges back and forth, a valve for controlling the air intake to said locking flanges, and a stop valve operated by the control valve to interrupt selectively the air intake to said jack, the improvement comprising; a two position selector mounted between the control valve and stop valve, said control valve including two fluid outlets each opening and closing in correspondence to the movements of the press, the opening of one outlet being accompanied by the closing of the other outlet, one of said outlets connected to said locking flanges and to said stop valve, and the other outlet connected to the stop valve, and said selector selectively blocking the intake of the fluid to the stop valve from each of said outlets in accordance with the position of said stop valve. 

1. In a device for feeding strip material to a press having two locking flanges for alternately locking the strip, a jack for moving said flanges back and forth, a valve for controlling the air intake to said locking flanges, and a stop valve operated by the control valve to interrupt selectively the air intake to said jack, the improvement comprising; a two position selector mounted between the control valve and stop valve, said control valve including two fluid outlets each opening and closing in correspondence to the movements of the press, the opening of one outlet being accompanied by the closing of the other outlet, one of said outlets connected to said locking flanges and to said stop valve, and the other outLet connected to the stop valve, and said selector selectively blocking the intake of the fluid to the stop valve from each of said outlets in accordance with the position of said stop valve. 